Stretchable, flexible material has been used for many years to form containers. For example, in the 1940's oleomargarine was packaged in bags made of polyethylene. In some cases, the user squeezed and manipulated the bag to rupture a color capsule and kneaded the bag to disperse the color throughout the margarine content. To disperse the contents, the user would cut or tear off a corner of the bag.
More recently, milk and other liquids have been packaged in polyethylene bags for the household commercial market. Again, the user cut or tore a corner off of the bag when the user wished to dispense the contents. There was no provision for reclosure of the cut or torn corner of the bag.
Large polyethylene bags up to 5 gallons have been used for the commercial institutional market, such as for hospitals, luncheonettes, etc. In these larger bags, a flexible hose was sealed into the bag with the outer end of the hose sealed closed. The whole bag was loaded into a dispenser with the hose extending through a pinch valve. The sealed outer end of the hose protruded from the dispenser valve so that the user could cut off the sealed end of the hose. Thus, the bag was reclosed by pinching the hose flat using the mechanical valve mechanism of the dispenser. There was no way to reclose such a large bag by itself after the sealed end of the hose was cut off.
For some years, intravenous liquids for hospital use have been packaged in polyvinyl chloride bags using tubes sealed into the bags with the outer ends of the tubes being sealed off. The sealed ends of these tubes are cut off to dispense the intravenous liquids and also to provide access for adding medicinal substances to the liquid content. More recently, such intravenous bags have been made with additive ports and with administrative ports which are sealed into the side wall of the bag.
For many years there has been a long felt need for a practical inexpensive nozzle outlet in stretchable, flexible container walls. It has been proposed to provide a nozzle outlet in the plastic film wall of a container by using an elongated rigid inner sleeve having a ridge extending around the exterior of the sleeve approximately midway between the ends of this elongated sleeve. A rigid outer member providing an inwardly projecting rounded shoulder having a smaller internal diameter (I.D.) than the external diameter (O.D.) of the ridge is forced over the peak of this ridge for clamping a very narrow portion, essentially a line contact portion, of the plastic film between the inner sleeve and the outer member at a position located beyond the peak of the ridge. This outer member may take the shape of a rigid O-ring, and thus the inwardly projecting rounded shoulder is provided by the inner surface of the O-ring. Thus, it is seen that only a very narrow localized portion, essentially a line contact portion, of the plastic film is clamped beneath the O-ring, which causes a stress concentration in the plastic film with a resultant weakening of the plastic film wall at the nozzle outlet. In addition, there is a severe stress concentration and shearing cutting action which occurs as the rounded shoulder of the outer member is forced over the peak of the ridge on the inner sleeve. Tearing of the plastic film wall sometimes occurs as this rounded shoulder is forced over the peak of the ridge. Sometimes induced stresses in the plastic film wall are so great that it spontaneously tears itself subsequent to installation.
The present invention advantageously overcomes all of these problems of the prior art and advantageously provides an inexpensive, practical nozzle outlet in a stretchable, flexible wall for a container.